I don't know that much about the Explorer, but I can tell you this much :
The Journey is essentially a Voyager with a full length running bottom and a slightly different aft lay -out. I don't think the Voyager and Journey hulls are different otherwise. I can also tell you the '98 and up hulls all use rot resistant wood in the transom and stringers.
As for which is better - My guess would be the Journey. They not only lengthened the running bottom to the transom to provide more buoyancy for 4 strokes, but to also improve performance. Our Voyager is difficult to trim for best performance with slight changes in load and sea conditions. I have been told the Journey is less sensitive.